This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The DiDAC system is now in routine use on four LANL flow cytometers (two phase sensitive flow cytometers, the three-laser system and the rapid mix kinetics cytometer) as well as on the demonstration flow cytometer used to teach a lab on instrumentation principles during the Annual Course in flow cytometry taught in part by the NFCR staff. All the DiDAC systems are running on the Intel platform under the LINUX 6.1 operating system. This system has revolutionary capabilities for very fast and sophisticated control of the operation of all of our cytometers, as well as four-way sorting and waveform recording of the raw data pulses. The design of DiDAC I has been frozen and design of a new generation data acquisition system has begun. DiDAC I uses technologies that are ~6 years old resulting in physically complex modules. One objection of commercial flow cytometer manufacturers to DiDAC I has been that each detector requires an expensive, large format board. Drawing on the experience gained in the DiDAC I development, design of a second-generation system is well underway. The prototype circuit boards will be fabricated by the end of the Resource year. DiDAC II is built around a commercial digital signal processor board that has a stackable bus format. The NFCR designed boards that contain the analog to digital converters and associated circuitry will plug directly into the stack. Boards for four detectors will fit in a 4 x 6 x 6 inch volume. Use of a programmable DSP processor enables a high degree of flexibility in signal processing via software that is not available in DiDAC I.